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Clean install Big Sur through Internet Recovery
- Thread starter chkwong
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I upgraded to Big Sur first; then used Cmd + R (instead of Cmd + Option + R) and it allowed me to perform a clean install.
If you're looking to do a true clean install of Big Sur right now, you're going to want to create a bootable Big Sur installer on a USB drive.
9to5mac.com
Make sure to read the instructions about temporarily disabling the secure boot settings, though, as your 2018 Mac mini has a T2 security chip.
This will let you fully erase the internal hard drive before installing Big Sur.
How to create a bootable macOS Big Sur USB installer drive - 9to5Mac
This tutorial shows you how to create a bootable macOS Big Sur USB installer drive, which can be handy for performing fresh installs on your Mac.
9to5mac.com
Make sure to read the instructions about temporarily disabling the secure boot settings, though, as your 2018 Mac mini has a T2 security chip.
This will let you fully erase the internal hard drive before installing Big Sur.
Can I ask whats the best way to clean install without the Mac installing the macOS it came with whats the difference with option command r or shift option command r what one is better for a clean install after format but I want to install the latest version not the one the Mac came with
option command r ： install latest macOS compatible with your Mac, but may require boot rom update first
shift option command r: install macOS that ship with your Mac
I have the 16" 2019 MacBook Pro whats the boot rom if I delete the partition and use option command r to get the latest version would it install or would I have problems, I dont wanna install Catalina first
you could create bootable USB installer...
then boot from usb, will see "a software update is required to use this startup disk" which will update the boot rom
then use option command r to go into Big Sur internet recovery mode
then install Catalina first, then update Big Sur from Catalina, then internet recovery to clean install again
Your previous betas may have updated your boot rom, so CMD + OPT + R works for you
Alternative Solution :
Simply restore the image as shown in the video to a USB stick and then use the option key to select the boot option.
Ignore the step or the note about EFI, this is not necessary on a real Mac.
Original Thread with everything you need Inside: https://www.hackintosh-forum.de/forum/thread/51323-macos-big-sur-internet-recovery-installer/
Simply restore the image as shown in the video to a USB stick and then use the option key to select the boot option.
Ignore the step or the note about EFI, this is not necessary on a real Mac.
Original Thread with everything you need Inside: https://www.hackintosh-forum.de/forum/thread/51323-macos-big-sur-internet-recovery-installer/
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I created a USB bootable drive and did a clean install of Big Sur. It just erased the system volume and not the data/app volume. I did have to update the boot rom. I had some problems with the install and have some file issues. I would now like to do a complete clean install (erase both system and app/data volumes) via Internet Recovery. Since I already have Big Sur installed can I just use CMD + R? Will it erase both volumes before the install?
CMD+R should be fine since Big Sur installed
go to disk utility, erase volume group
then clean install
I've just got a 2020 iMac 27inch which is my first Mac and apple device. Its come with Catalina, I don't see much point in trying to get used to that with Big Sur out. I may as well go straight to that, I know with windows I always liked to do a clean install, but with Macs I've no idea were to start. What is the easiest way for me to just do a clean install, I don't need to save anything, and do I type commands into a terminal or do I boot into a different mode, I'm very much on a steep learning curve 
If you just got the machine, there really is no reason to do a clean install. MacOS is not fragmented like Windows. I recommend just doing the update to Big Sur.I've just got a 2020 iMac 27inch which is my first Mac and apple device. Its come with Catalina, I don't see much point in trying to get used to that with Big Sur out. I may as well go straight to that, I know with windows I always liked to do a clean install, but with Macs I've no idea were to start. What is the easiest way for me to just do a clean install, I don't need to save anything, and do I type commands into a terminal or do I boot into a different mode, I'm very much on a steep learning curve
